1. Field of the Invention
The present invention relates to a digital camera, and more particularly, to the improvement of a single-lens reflex digital camera capable of displaying on a display screen both an image being viewed and an image being shot.
2. Description of the Related Art
Cameras are commonly known, which form an optical image of a subject on an image pickup device from light coming from the subject and passing through a photographing optical system, photoelectrically convert the optical image into electric image signals through the image pickup device, and display the resulting image on the screen of an image display device, such as an LCD monitor, based on the electric image signals.
As an example of such digital cameras displaying a subject image, there is known a type of camera, which is provided with an image pickup device for monitoring a subject field, that is, for displaying a live view (a real-time moving picture), separately from an image pickup device for actual exposure. In this type of camera, a half mirror is arranged in a finder optical system to guide a light beam of the subject to the image pickup device for live view display. In a live view mode, the image pickup device for live view display repeats imaging to display a live view on a display device (for example, see Japanese Patent Laid-Open No. 2000-165730).
Suppose here that a bright lens having a small f-number or a telephoto lens is mounted on a lens-interchangeable single-lens reflex digital camera (hereinafter simply called an “SLR camera”) as one type of digital camera. In this case, if the sun is included in a frame, it could cause damage to an imager. Especially, an SLR camera with live view capability is more likely to damage its imager because the imager continues to be exposed during framing.